Raspberry plant cv. `Isabel`

ABSTRACT

A new and distinct variety of red raspberry plant named `Isabel`, which is particularly characterized and distinguished by its consistently large size fruit of excellent flavor and color and its high yielding capacity on both primocane and floricane crops.

BACKGROUND AND SUMMARY OF THE INVENTION

This invention relates to a new and distinct cultivar of raspberry plant that has been given the variety name or denomination `Isabel`. The new cultivar was developed from hybridization of the selection B36.7 (an unpatented variety) as the seed parent with the selection C44.1 (an unpatented variety) as the pollen parent. The parents were crossed by Stephen Wilhelm in 1987, whereafter fruit and seed were collected to produce seedlings for field planting in Watsonville, Calif., in 1988. The new variety was selected from these seedlings by Carlos Fear in 1989 for their large, attractive fruit. Since its selection the `Isabel` plants have been evaluated in several noncommercial experimental plantings in Watsonville, Calif. The `Isabel` variety has been asexually propagated by in vitro shoot tip culture, root sucker division and root cuttings, and has been shown to maintain the desired and distinguishing characteristics after propagation over several generations.

The `Isabel` raspberry plant produces a relatively early primocane crop which begins in July and continues until late October. The floricane crop begins in early May and continues until about mid-July. Both the primocane and floricane yields are high relative to other comparable varieties. The fruit of the `Isabel` raspberry plant is large and remains consistently so throughout its harvest period. The fruit has a very pleasant flavor and darkens only slightly after harvest.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a photograph of an `Isabel` floricane mature leaf and fruiting shoot, showing various stages of fruit development.

FIG. 2 is a photograph of an `Isabel` primocane shoot.

FIG. 3 is an interpretative drawing showing the cultivar banding patterns for the enzymes, MDH (malate dehydrogenase), PGI (phosphoglucoisomerase) and PGM (phosphoglucomutase).

DETAILED DESCRIPTION OF THE PLANT

Throughout this specification, color names beginning with a small letter signify that the name of the color, as used in common speech, is aptly descriptive. Color names beginning with a capital letter designate color values based on The R.H.S. Colour Chart published by The Royal Horticultural Society of London, England.

The following description is a detailed description of the `Isabel` raspberry cultivar and the fruit produced thereby, as grown in Watsonville, Calif. between 1991 and 1994, and is believed to apply to plants of the `Isabel` variety grown in similar conditions of soil and climate elsewhere.

The `Isabel` fruit size is large and does not decline as much as most varieties throughout the fruiting cycle. Fruit color darkens only slightly after harvest. The fruit of the `Isabel` plant is average or moderate in its ease of separation and of moderate firmness at harvest. Post harvest fruit rot resistance is intermediate in comparison with many selections and varieties.

The `Isabel` variety has moderate susceptibility to late leaf rust and powdery mildew. Resistance to root rots is unknown and cold tolerance of the new variety has not been established.

The new variety is particularly characterized and distinguished from other cultivars by it high yields on both primocanes and floricanes. It is further distinguished by its large, bright red fruit of excellent flavor, which maintains its large size through the harvest season. The `Isabel` variety also fruits earlier in the spring than most other cultivars.

`Isabel` is distinguished from its pollen parent, selection C44.1, by fruiting earlier in the spring, having larger fruit size, and yielding more fruit. The new variety is distinguished from its seed parent by having a higher yielding capacity with more uniform fruit shape.

Tables 1 and 2 below present morphological information about the new `Isabel` raspberry cultivar.

                  TABLE 1                                                          ______________________________________                                         PLANT CHARACTERISTICS OF `Isabel`                                              ______________________________________                                         General                                                                        Plant size:             medium                                                 Growth habit:           erect                                                  Density of foliage:     medium                                                 Productivity:           very productive                                        Self fruitfulness:      self fruitful                                          Primocane fruiting:                                                            percent of cane length  about 40-50%                                           flowering as primocane:                                                        percent of total yield  about 45-50%                                           from primocane crop:                                                           Suckering tendency:     medium                                                 Utility of fruit:       various                                                Canes                                                                          Primocanes                                                                     Number of fruiting laterals/cane:                                                                      many/about 15-20                                       Number of canes/crown:  few/about 4-7                                          Young shoot pigmentation:                                                                              weak                                                   Length:                 about 69-84"                                           Diameter (end of 1st year):                                                    cane base:              about 0.40-0.78"                                       central 1/3 of cane:    about 0.31-0.62"                                       Depressions in cross section:                                                                          absent                                                 Prickles:                                                                      pigmentation:           pigmented                                              density on young shoots:                                                                               medium                                                 attitude of tip:        horizontal                                             size:                   medium                                                 texture:                rigid                                                  presence and            uniformly                                              distribution on petioles:                                                                              distributed                                            Pubescence on canes:    absent to very                                                                 slight                                                 Internodal distance     about 1.5-3.0"                                         (at central 1/3 of cane):                                                                              (1.9" mean)                                            Lenticels:              not visible                                            Floricanes                                                                     Length:                 about 48-72"                                           Number lateral branches per cane:                                                                      about 6-16                                             Number nodes/lateral (at mid cane):                                                                    about 11-15                                            Number of flowers/node  about 2-5                                              (at 4th node from apex                                                         on a mid cane lateral):                                                        Leaves                                                                         Arrangement:            compound                                               Relief between veins:   medium                                                 Leaflet number:         3-5, usually 5                                         Terminal leaflet:                                                              length:                 about 4.9-6.5"                                         width:                  about 3.7-5.7"                                         shape:                  ovate                                                  tip:                    acuminate                                              base:                   cordate                                                margin:                 doubly serrate                                         Lateral leaflets (basal pair):                                                 overlap:                touching to                                                                    slight overlap                                         orientation:            opposite                                               shape:                  oblique                                                tip:                    acuminate                                              base:                   oblique                                                margin:                 doubly serrate                                         length:                 about 4.3-5.8"                                         width:                  about 3.2-4.0"                                         Rachis length between   about 0.75-2.1"                                        terminal leaflet and                                                           adjacent lateral leaflets:                                                     Color:                                                                         face:                   Green 137A-137B                                        underside:              Green 191B                                             Petiole:                                                                       length:                 about 4.5-7.3"                                         pigmentation of upper surface:                                                                         often pigmented                                        pigmentation of underside:                                                                             unpigmented                                            Stipule orientation:    erect                                                  Flowers                                                                        Flowering period:                                                              primocane:              early June to                                                                  late October                                           floricane:              early April to                                                                 mid-June                                               Petal:                                                                         color:                  White 155B-155D                                        length:                 about 0.22-0.28"                                       width:                  about 0.12-0.16"                                       number:                 5                                                      arrangement:            free                                                   Pedicel coloration:     weak                                                   ______________________________________                                    

                  TABLE 2                                                          ______________________________________                                         FRUIT CHARACTERIZATION OF `Isabel`                                             ______________________________________                                         Fruit                                                                          Harvest season:                                                                primocane:           early; begins                                                                  mid- to late July;                                                             ends late October;                                                             uniform ripening                                                               over a long period                                                             (about 90-100                                                                  days)                                                     floricane:           very early; begins                                                             early to mid-May;                                                              ends mid-July;                                                                 ripens uniformly                                                               over a long period                                                             (about 60 days)                                           Color:                                                                         immature:            Red 39A                                                   maturing:            Red 47A-47B,                                                                   glossy                                                    mature:              Red 53B                                                   Dimensions:                                                                    weight:                                                                        primocane harvest:   about 3.7-5.4 g                                                                (4.5 g mean)                                              floricane harvest:   about 3.4-5.1 g                                                                (4.4 g mean)                                              length (primocane):  about 0.66-0.94"                                          width (primocane):   about 0.63-0.81"                                          Soluble solids (%):  about 8.5-9.1%                                                                 (8.8% mean)                                               Titratable acidity   about 1.5%                                                (% as citric acid):                                                            Seeds:               about 1.1-1.6 mg                                          weight:              (1.3 mg mean)                                             Number drupelets/fruit:                                                                             about 76-118                                                                   (101 mean)                                                ______________________________________                                    

In addition to the foregoing morphological description, and to provide further means for identifying the new variety and distinguishing it from some other somewhat similar and/or related raspberry varieties, the new `Isabel` variety has been analyzed to obtain an indication of its genetic makeup. Specifically, leaves of the `Isabel`, `Hollins` (U.S. Plant Pat. No. 8,027), `Summit` (unpatented), `Wilhelm` (U.S. patent applied for), `Sweetbriar` (U.S. Plant Pat. No. 4,486), and `Joe Mello` (U.S. Plant Pat. No. 6,493) varieties were electrophoretically analyzed, the patterns designated and procedures utilized being per those described by J. C. Cousineau and D. J. Donnelly, "Use of Isoenzyme Analysis to Characterize Raspberry Cultivars and Detect Cultivar Mislabeling," HortScience, vol 27 (9):1023-1025 (1992). The results of the electrophoresis analysis are presented in Table 3 below, the letters representing the cultivar banding patterns for each enzyme as shown in FIG. 3, taken from the above article.

                  TABLE 3                                                          ______________________________________                                         ISOZYME BANDING PATTERNS OF `Isabel`                                           COMPARED WITH `Hollins`, `Summit`, `Wilhelm`,                                  `Sweetbriar` AND `Joe Mello`                                                            Isozyme and Pattern                                                   Cultivar   PGI          MDH     PGM                                            ______________________________________                                         `Isabel`   A            E       C                                              `Hollins`  D            E       D                                              `Summit`   A            C       B                                              `Wilhelm`  D            A       C                                              `Sweetbriar`                                                                              D            D       A                                              `Joe Mello`                                                                               D            E       C                                              ______________________________________                                     

We claim:
 1. A new and distinct variety of raspberry plant named `Isabel`, as herein illustrated and described. 